Electromagnetic relay structure



United States Patent Primary Examiner- Harold Broome Attorney-Harold S. Wynn ABSTRACT: This electromagnetic relay is of the safety-type as used by railroads. It has parts molded of black fiber glass plastic material and has other parts formed of metal and constructed to be assembled in such a way as to provide a composite structure requiring no adjustment after initial assembly. The armature is'mounted on a knife edge bearing with the working airgap at the rear of the relay and the contact operator at the front of the relay The plastic cover holds a magnetic back yoke in place for connecting the two magnetic core members, which back yoke is directly removable when the cover is removed so as to be able to replace the coils without further disassembly. The coils have quick detachable connectors which connect to the coil lead fingers at the front of the relay. The contact fingers are pushed into position from the front of the relay with the cover removed and a guide block is permanently provided for assisting the entry of the contact fingers into the rear mounting block into which such fingers automatically lock when they are placed in position.

PATENTEDDEBISIQYB 3.548.139

' SHEET 1 OF 4 FIG. I

INVENTORS W. D. MAYNARD E. A. BELANGER( THEIR ATTORNEY SHEET 2 BF 4 FIG. 3

FIG. 2

E @3@ @029 U E 3 E k @o o @o 0 Q INVENTORS W. D. MAYNARD E. A. BELANGER m fmw THEIR ATTORNEY PATENTEU DEC] 5 I970 FIG. 4

SHEET 3 BF 4 ZSE m E29 0 Q Lu 0 FIG. 5

:ifizrj INVENTORS lil/ w.,0 MAYNARD E. A. BELANGER BY I THEIR ATTORNEY Pmmiunmsmm 3.548.139-

' SHEET 0F 4 FIG. 7

INVENTORS W. D MAYNARD E. A. BELANGER BY W THEIR ATTORNEY readily disassembled in part for This isa division of the application of Wheeler Maynard and Edward A. Belanger, Ser. No. 681,209Qfiled Nov. 7,

1967, which has resulted in US. Pat. No. 3,509,502, issued more particularly to'an electromagnetic relay assembled from a multiplicity of parts and constituting-an operable relay when once assembled without further adjustment, I I

l-leretofore, electromagnetic relays-of.the safety type h'ave been built which are highly efficient,- but. most ekpensive' to manufacture. One of the reasons for the expense in manufacture is that the relay requires a fine adjustment after initial as sembly in order to be properly operative-Also, such fineadjustment of the relay tends to deteriorate and reduce the life of therelay.

The present invention relates to a safety-type relay which has a gravity biased armature for operating the contacts, which armature is additionally biased by a suitable coil spring so as to minimize its response to vibration-and bounce, and also to maintain its-operability uniform over along life. The armature operates the contact fingers of the relay through a contact pusher member connected to the contacts directly in line with their contact' points to directly'oppose any tendency to stick due mfusion effects .that might'de'velop through the relay op'erationyand a'lsoto avoid the variable deflection of the contact fingers.

Thus, the purpose of the present invention is to provide an improved safety relay which doesnotrequire adjustment after the initial assembly, and which is easily andrapidly assembled from parts that can be mass produced and yet nieet the rigid requirements necessary for safety operations. j I

Another object-of the present invention is to provide. an improved relay assembly wherein the parts are readily assembled into precise positions due to the typeof manufacture of the parts so as to provide the desired operating characteristics which are insensitive to minor production variations.

A further object of the invention is to provide a relay having an efficient magnetic structure which can be quickly and the replacement of the coils on the relay. I I I I I I I SUMMARY ormvsnnon in general, the relay of this invention includes a' housing structure having the shape of a, parallelepiped with rectangular relay to show the form of the 3 is aback view of the'structure shown in FIG. 1 illustrating more particularly the slotted contact-mounting block and the coded back cover forthe electromagnetic portion of l the relay;

- FIG. 4 is a front view of the housing structure only of the structure :to which all of the other parts are related; I

' I FIG. S-is a side sectional view of the housing structure shown in FlG. 4; I

FIG. 6 is an enlarged side view. of the armature and its knife edge bearing;

FIG. 7 is an enlarged top view of the arrnatureand its knife edge'bearing as'shown in FIG. 6;

FlG.-8 shows a front view of the contact-pusher member shown in side view in FIG. 1; and

FIG. 9'is' a top view of the-front cover as mounted on the housing structure and which is held in place on a terminal board by a wire bail fitted over the handle on the cover and extending to the two recessesv in the terminal board.

Generally speaking, the electromagnetic relay of the present invention is-compn'sed of a molded frame or housing structure 19 which encloses the variouspans and to which a transparent cover 11 is attached; Inside the upper portionof bases, a lattice structure located inside the-front of the housing structure and integral therewith, the lattice structure having at one end-matching the spaces in the lattice structure and with openings at the other end matching theslots in the contact-mounting block.

For abetter understanding of the present invention togetherwith other and further. objects, thereof, reference is made to r the following description, taken in connection with the accompanying drawings, while its scope will'be pointed out in the appended claims..

I J IN THE oRA'wiN cs FIG. I is a side elevation partially section taken on lines 14 of FIG. 2 which shows the parts of-the electromagnetic relay constituting the structure of the present invention;

H6. 2 is a front view with the cover 'of'the relay removed and with parts shown in s'ection to illustrate the assembly shown in FIG. 1;

structure provides rigidity to the housing. The back upper porthe housing, the contact assembly'is located, and in the lower portion of the housing, the electromagnetic structure is located.

The armature 35 is mounted on a knife edge bearing 31 rivetedonto the housing between the upper and lower portions of the housing and near its back, The armature 35 is L- 'shaped and hasa portion or am which cooperates with they two-pole faces 33 and 34 of the two-cores 30 which are rigidly attached to the housing structure. There is, also a contactoperating portion or arm 35A of the armature which extends towards the front'of the housing between its upper and lower portions.

The knife edge bearing 31, the armature 35, the cores 30 and the coded back plate-36 are assembled and riveted. in place in the housing at the same time-on the two vertical bosses 15 located one on each side of the lower portion of the housing-The contact-operating portion ofthe armature 35A rests at its forward end against the upper side of a cross-bridge 18. arranged in the form of an arch connecting the two sides of the housing 10. Also, a flat cross -bridgeinember 16 is located .at the back of the housing connecting the tops of the two vertical'bosses 15. There are two horizontal'ribs' l9 connecting with the two vertical bosses and extending forward to the arched cross bridge. in a similar fashion, two horizontal ribs w 21 extend frornthe vertical 'bosses forwardto a flat crossbridge 20 at the front of the housing located between the space allotted to the cores and coil members of the electromagnetic structure.

The first-mentioned flat cross-bridge l6 at the back of the housing and connecting the tops of the two vertical bosses 15 has a downwardly extending abutment 14 running crosswise directly abovethe armature on its knife edge bearing and acting to hold the armature downwardly on such knife edge bearmg. I I I At the front of the 'upper portion of the housing is a honeycomb-or lattice structure for providing back stops for certain fixed contact fingers and providing supports for the coil springs located to supply the bias tosuch fixed contact fingers. This honeycomb orlattice also has a back stop for the coil spring which biases the armature "toa -normal position against the arched cross-bridge 18. In addition, this lattice tion .of they housing-is open so as to receive a contact guideblock 40 which is also of a honeycombforrn. In addition,

a rear contact-mounting block 42 is provided with suitableslots and is bolted into position following the insertion of the contact guide block 40.

The contact fingers, such as finger '39, are moved into position from the front of the housing. 'As they enter their respective spaces in the lattice structure at the front of the housing,

they also enter the respective chutes, such as chute 44, in the contact guide block which guides the end of the finger to enter' the appropriate slot in the contact-mounting block 42 at the rear of the relay. As a small portion of this contact 39 extends out of the slot at the rear of the mounting block 42, a tool is used to grasp the extending end and pull it rearwardly until the contact finger-locking member 45 springs downwardly and engages the side of the slot in the block 42. When all the contact fingers are in position, the coil springs 41 are inserted into the lattice structure in a way to bias the fixed contact fingers against their respective stops in the lattice structure. Also, the coil spring 48 for biasing the armature is placed in position in the lattice structure.

Assuming that all of the contact fingers are in appropriate positions, the contact pusher member 51 is mounted over the armature arm 35A and each movable contact finger is inserted in the respective slots in the pusher member 51. When the pusher member 51 is appropriately located, a lock finger 53 is then slipped into position through the slot in the pusher member 51 and through the contact guide block 40 and into the rear contact-mounting block 42 until it is locked into position. This lock finger 53 has projections at the front which extend to the right and left as viewed from the front so as to hold the contact-pusher member 51 in position against the rear projections on each of the movable contact fingers mounted in the pusher member.

The test fingers 64 are provided with narrow projections at each enILEach finger 64 may be slid into its appropriate position in the slide runways provided at the base of the relay. The two coils 28 on suitable plastic spools 38 are inserted over the cores 30 and moved into their positions. Their lead wires come out at the front of the relay for attachment to the lead fingers 49 located at the sides of the lattice structure. The quick detachable connectors 50 actually insert through a suitable space in the pusher member 51. When this has been done a back yoke 62 is fitted onto the two extending cores 30 with such back yoke 62 having holes for receiving the cores which provide a smooth and accurate fit with the core members. The cover 11 is then positioned over the front of the relay to enclose the electromagnetic portion and the contact assembly. A spring 63 is located in the cover to hold the back yoke tightly in position on the cores. The placement of the cover 11 also receives the ends of the test fingers 64 through slots in the cover.

A flat cross-bridge 69 in the cover 11 fits appropriately just about the winding lead connectors 50 to separate them from the movable contact fingers extending through the contactpusher member. Such cover is held in position by suitable screws inserted into appropriate recessed holes in the corners of the cover and extending into the housing member at its four corners. The relay is then ready to be fitted into a suitable terminal board.

More specifically and with reference to FIG. 1, the electromagnetic relay structure is shown in a side elevational view with certain parts in section as taken ingeneral on lines 1-1 of FIG. 2. This relay comprises a housing structure 10 and a cover member 11. The housing structure 11) is shown with a front view in FIG. 4 with all parts removed and in a side sec- .tional view taken .on lines 5-5 in FIG. 5 also with all parts removed.

Referring to FIG. 4, the housing structure is molded of a fiber glass filled resin in a single piece in the form of a rectangular boxlike shape sometimes termed a parallelepiped with rectangular bases. Such molding includes different compartmental separations and structure to give added strength and rigidity to the structure, as well as providing certain functions broadly explained above.

In FIGS. 4 and 5, it can be seen that the housing structure 10 has inwardly extending vertical bosses along the rear inside edge on both sides. At the top of these bosses 15 is a cross-bridge 16 which is fiat and extends between the two sides of the housing 10. An upstanding central boss 17 is provided for receiving a screw. Around the inside of the wall of the housing 10 adjacent the rear edge is a depressed strip making the wall of the housing slightly thinner. This makes a recess for receiving the slotted contact-mounting block 42. This block 42 has screws inserted in the boss 17 at the bottom of the upper space or portion and also inserted in the two bosses 66 at the top (see FIG. 4). Therefore, the top floor of the cross-bridge 16 is raised slightly, on each side of the boss 17; and similarly the underside offthe same portion is slightly raised. The abutment 14 joins these two levels underneath and extends downwardly an appropriate amount to meet the top of the armature. In FIG. 4, it can be seen'that the lower edge of the abutment 14 is very slightly curved downwardly (see thick line) in the center just a sufficient'amount to just barely clear the armature. This allows the armature to ride flat on its knife edge bearing 31 without binding as seen in FIG. 1, and yet be properly held in position.

At the front of the housing 10 is an arched cross-bridge 18 which extends from side to side. Running alongeach side of the housing 10 on the inside are ribs 19. Each of these ribs 19 connects the arched cross-bridge 18 with the corresponding vertical boss 15 on its side of the housing. To give added strength, the ribs 19 have raised edges near the front and leading into the sides of the upper floor of the arched cross-bridge 18 as best seen in FIG. 5.

Another flat cross-bridge 20 connects the sides of the housing 10 at the front thereof, and this cross-bridge 20 also has ribs 21 extending backwardly along the sides to the corresponding vertical bosses l5.

At the bottom of the housing 10 is a compartment for receiving the test fingers 64 which compartment is provided with the enclosing flat bridge 22 locate'd at the bottom of the vertical boss 15. A vertical rib 23 near the center of the compartment runs the length of it to give stability. Similar ribs 29 are located at each side of the compartment for the same reason. Within the two smaller compartments are pairs of grooved ribs 24, 25 and 26. At the back of this lower compartment, located a short distance inwardly is a horizontal enclosing rib 27 having three vertical slots seen in FIG. 4.

The upper portion of the housing structure 10 is a honeycomb or lattice structure which forms the backstops 70 for the fixed contacts and also the seats 71 for the coil springs biasing such contacts. Spaces 72 are also provided for the movement of the movable contacts. At the bottom of this honeycomb there are two grooved spaces 73 for receiving pairs of coil connector fingers. A seat 75 is also provided for the armature-biasing coil spring 48. In the four corners of the housing 10 are bosses for receiving self-tapping screws adapted to secure the cover 11 in place.

The inside of the honeycomb or lattice structure has two further inwardly projecting ribs -76 for giving added strength to v the lattice structure and also for limiting the inward position of the contact guide block 40. These two ribs 76 extend downwardly from the top of the housing 10 to the slot 77. An intermediate slot 78 also connects the two vertical ribs 76 which are in line from the front of the lattice structure to the near midportion of the contact compartment.

With the above general understanding of the housing structure, it can be readily seen that the cores 30 can have their pole pieces 33 and 34 fitted into recesses in the vertical bosses 15. Also, a knife edge-bearing plate 31 can be placed in the recess between the cross-bridge 16 and the ribs 19, so as to receive the armature 35. The coded back plate 36 is placed over the compartment and rivets 37 are slipped through the pole pieces 33 and 34, the bosses 15 and the coding plate 36. The flattening of the heads of these rivets 37 thus secure the core pieces 30, the armature 35 and its bearing 31, the coded back plate 36 in position. The core pieces 30 thus extend outwardly towards the front of the housing 10. The armature 35 has two vertical slots, one on each-side, which are slightly wider than the bearing strip 31 (see FIG. 6). The position shown in FIG. 6 is with the armature in its attracted position at residual strips 80 on the pole faces. Such strips are placed on nectors 50.

magnetic permeability.

the pole faces just before they are fitted into the vertical bosses 15. With the armature in this position, the entire slot of the armature is required for the sides of the bearing which merely enter the slots which is best seen in FIG. 7. The righthand side of the bearing plate is in exact alignment with the left side of the armature. The coil button 46 is also slipped into its receiving hole in the armature 35A;

The contact guide block 40 is slipped into the upper portion of the housingstructure l0 and is held in position against the back of the lattice structure by placing the contact-mounting block 42 in position where it. is held byinserting three selftapping screws 43.

The fixed contact fingers 39 are slid into appropriate spaces in the lattice structure and enter the contact guide chute 44 in the contact guide block 40. Upon the further insertion of the contact, it is guided to enter its slot in the mounting block 42. 1

When a sufficient portion of the finger exits through the slot in the block 42, a tool is inserted intothe recess at the rear of block 42 adjacent the slot and is used to pull it through'until the lock finger 45 springs downwardly and holds the contact'in place. This fit of the contact 39 in the block 42 is. snug and tight on both the upper and lower surfaces of the contact and particularly so with regard to the side edges. It is the snug slot in this block plus the continuing longitudinal sliding portions into the block which determine the rel'ativelyexact perpendicular projection of the forward end of the contact finger 39.

When the fixed contacts are positioned, then the movable contacts 59 are similarly slid into their positions where they look in place. When all of these contacts are in position, suitable coil springs 41 are placed on their seats in the lattice structure for biasing the fixed contacts to their appropriate normal positions; In addition, insulatedseat 46 isinserted intoja hole 47 in the armature and a biasing spring 48 slipped into position onto the two opposing seats 46 and 75'. i

The winding connector fingers'49 are slipped into position the same as the other contact fingers, but these contact fingers merely extend forwardly for receiving quick detachable con- When 'all of the fingers have been placed in position, the contact pusher member 51 shown in front view of FIG. 8 is positioned over the armature arm 35A and gently laid against .the movable contacts which may need slight adjustment in order to enter the slots in the extending fingers 91 and 92 of the contact pusher member. These fingers 91 and 92 grasp each of the movable contacts exactly opposite their contactmaking points so that such contacts are. forcibly moved by operation of the armature removing anytendency of the contacts to burn closed as the pusher member 51 is moved by the armature. I

When the pusher member 51 is moved inwardly so that it when the cover is placed in position. The test fingers 64 may have to be slightly ad usted to enter their respective slots In the cover.

When the cover is in position, the screws 65 are inserted to hold the cover 11 onto the housing 10. When the relay is thus constructed, it is complete and ready for operation. I

To place it in operation, it is merely mounted on a plug board adapted to receive its projecting co'ntact fingers and having coded projections to enter the coded holes in the coded back cover 36. .A wire bail 60 is connected in the slot on the terminal board and is sprung over the outer handles 81 of the relay as shown in FIG. 9. In this way the relay is held on the terminal board and is removable when desired.

It is noted that FIG. 8 shows an enlarged front view of pusher member 51 which can also be found in FIGS. 1 and 2. This from view shows the extending lips 91 and 92 which take hold of the contact fingers directly adjacent the contact points as can also be seen in FIGS. 1 and 2. Also,'mild shading is shown in areas of FIG. 8 to illustrate the thin webs 93 of molded material between major portions or bars of the material. These thin web portions 93 act to give strength and stability to the pusher member 51. The Iargerfingers. 94 act to grasp the armature arm 35A as can be seen-in FIG. 2. (It is noted that one of these fingers 94 is omitted from FIG. 2.)

While there has been described what is at present considered to be the preferred embodiment of the invention, it will be obvious to those skilled in the art that various changes and modifications may be made therein, without departing from the invention; and, it is, therefore, intended that the appended claims shall cover all such changes and modifications as fall within the true spread and scope of the invention.

1. An electromagnetic relay having a plurality of contacts wherein the improvement comprises a housing structure having a shape of a parallelepiped with rectangular bases, a lattice structure located inside the front of saidhousing structure and integral therewith, said lattice structure having spaced openings for receiving the contacts, a guide block located in said housing structure abutting said lattice structure for guiding the insertion of the contacts into the relay structure, a slotted contact-mounting block located within said housing structure at the rear of said guide block, said slots being located to match the spaces in said lattice structure, and said 7 guide block having internal chutes with openings at one end abuts against the contact side extensions, then a lock finger 53 I is inserted which has projections at its outer end for holding the pusher member 51 in position. This lock finger 53 has the same kind of locking fingers 45 for the contact block 42.as previously described. I

The coils are wound on plastic spools 38 which readily slide over the core members 30 with thecoil ends suitably positioned and having the quick detachable contact members 50 attached at their ends. Thus, the two coils can be slipped over their respective cores 30 and their four terminals suitably connected to their respective fingers 49 rather quickly through appropriate spaces left in the contact pusher member 51. The outer ends of the spools 38.have a raised portion at one side. These raised portions are placed at the .top and the bottom of their respective spools so that a back yoke 62 can be slipped over the ends of the cores. This fit of the back yoke 62 is snug so as to make ready magnetic contact with thejcores 30. This back yoke 62 is molded from powdered magnetic material which is amalgamated into a unitary structure which has high matching said spaces in said lattice structure and with openings at the other end matching the slots in said contactmounting block.

2. A relay according to claim 1 in which contact fingers are mounted in said housing structure with one end of each finger fastened in said slotted contact-mounting block and with the other end of each finger being movable in its respective one of said spaced openings of said lattice structure without interference by said guide block.

3. A relay according to claim 1 in which said slotted contact-mounting block has grooved slotsfor receiving flat contact fingers and causing them to be held in perpendicular position, the other end of each finger being capable of flexing in its chute of said guide block and in its opening of said lattice structure.

4. A relay according to claim 1 in which said slotted contact-mounting block has a recess to the rear of each slot, two parallel grooves in each said recess running from said slot to the rear of the said block, said slot and grooves of each recess holding its finger substantially perpendicular to said block and 

